This invention relates to the formation of conjugates, and in particular to the joining of one species to another at a carbohydrate or carboxyl moiety on one of the species, utilizing a thioether or disulfide bond as part of the linkage.
The linkage of compounds of various types to carbohydrate or carboxyl moieties is desirable for a variety of reasons. In the formation of conjugates involving immunoglobulins, for instance, linkage at specific regions on the immunoglobulin is often desirable for purposes of maintaining the accessibility of antigen-binding sites or of sites on the Fc chains for complement binding. As a further example, certain solid supports used in affinity chromatography have carbohydrate or carboxyl groups available for binding, and the same is true for other solid phase materials as well such as those used in two-phase immunoassays.
Many of the species which are sought to be linked to these carbohydrate or carboxyl moieties are species which lack the ability to react directly.